Area Forecast Discussion

WHAT HAS CHANGED

Updated key message 1.

KEY MESSAGES

- 1) Patchy dense fog this morning.

- 2) Unseasonably warm temperatures expected through late week, with scattered showers and perhaps a thunderstorm or two possible on Friday.

DISCUSSION

KEY MESSAGE 1: Patchy dense fog this morning.

Early this morning, IR nighttime microphysics RGB indicated an expanding area of stratus across portions of SE GA and the SC Lowcountry. Based on web cams and sfc based observations, patchy dense fog has developed across portions of the SC Lowcountry, highlighted with a Special Weather Statement until 7 AM. Near-term guidance has struggled with the timing, placement, and density of the fog this morning. We will continue to monitor the fog, if the coverage of dense fog increases, then a Dense Fog Advisory could be needed.

KEY MESSAGE 2: Unseasonably warm temperatures expected through late week, with scattered showers and perhaps a thunderstorm or two possible on Friday.

Mid level heights will lower late week as a larger scale trough shifts into the eastern U.S. At the surface, a weak front will slowly move towards the region, eventually getting pushed offshore later Friday or Friday night. Rain potential looks rather unimpressive. Despite increasing moisture, the best forcing passes to the north. Thursday could see an isolated shower, but most of the area will be dry. A bit higher coverage is expected on Friday with a weakening band of precip likely moving into the area during the day. Significant rainfall is not expected. Probabilities for rainfall greater than 0.25" are generally less than 20%, except slightly higher over interior South Carolina. Weak instability could support an isolated thunderstorm or two, but severe weather is not anticipated. Drier air returns following fropa, with a rain-free forecast in place for the weekend and early next week.

Outside of rain chances, the other forecast item of note is the unseasonably warm temperatures. Highs today through Friday are mostly in the low to mid 80s. These values are around 10 degrees above early November normals and are within a few degrees of records (see climate section below).

AVIATION /09Z WEDNESDAY THROUGH SUNDAY/

Prior to the 6Z TAFs, IR nighttime microphysics RGB indicated an expanding area of stratus across portions of SE GA as a band of mid and high clouds drifts north. Based on satellite trends, LIFR ceilings is expected to develop over KSAV by 7Z. The stratus may build down through the rest of the night, possibly leading to periods of MVFR fog and LIFR ceilings between 8-12Z, highlighted with a TEMPO. Lingering high clouds should limit the formation of restrictive stratus over KCHS and KJZI, but we will continue to monitor. However, as winds become light during the pre-dawn hours this morning, patchy fog or ground fog may develop over KCHS between 10-12Z, highlighted with a TEMPO. By mid-morning, a weak sea breeze should begin to push inland, resulting in winds to turn from the southeast and increasing to 10 to 15 kts at KJZI, KCHS, and KSAV.

Extended Aviation Outlook: Isolated to scattered showers, and possibly a thunderstorm or two, could impact the area Thursday and Friday. Any flight restrictions should be brief.

MARINE

Today through Tonight: The forecast pattern will support southeast winds generally between 10 to 15 kts across the marine zones. Seas will begin the day between 3 to 5 ft, decreasing to 3 to 4 ft tonight. All Small Craft Advisories have been removed from the forecast area.

Thursday through Monday: Conditions are expected to remain below Small Craft Advisory levels late week through the weekend. A cold front will approach the region and eventually push offshore Friday night. No significant wind surge is expected behind it. Speeds will generally top out at 15 knots with seas peaking 3-5 feet.

CLIMATE

Record High Temperatures:

November 4: KSAV: 85/2012

November 5: KCHS: 87/2003 KCXM: 81/1992 KSAV: 85/2003

November 6: KCXM: 81/2003

Record High Minimum Temperatures:

November 4: KCHS: 67/2015 KCXM: 69/1992 KSAV: 71/2003

November 5: KCHS: 69/2003

CHS WATCHES / WARNINGS / ADVISORIES

GA...None. SC...None. MARINE...None.